Device for automatized insertion of reaction tubes in test tube holders

ABSTRACT

A device is provided for insertion of reaction tubes, having projections or the like at the open end, into holders. The tubes are fed one at the time from a supply into which the test tubes are placed directly from the packages to a means in which guide means retard the falling action of the end having the projections so that the closed end of the test tube falls faster and so that the test tube will be placed in a vertical position with the open end upwards, in a test tube holder placed directly beneath the falling path. When the next tube is fed also the next empty holder is fed into position.

United States Patent Kjell Agner DEVICE FOR AUTOMATIZED INSERTION OF REACTION TUBES IN TEST TUBE HOLDERS 4 Claims, 3 Drawing Figs.

U.S. Cl 221/172 Int. CL... B6Sh 9/00 Field of Search 22 l/l56,

[56] References Cited UNITED STATES PATENTS 676,761 6/1901 Morris 221/156 X 2,824,361 2/1958 Brown 221/173 X Primary Examiner Samuel F. Coleman Assistant Examiner-John P. Shannon, Jr. Att0rneySommers & Young ABSTRACT: A device is provided for insertion of reaction tubes, having projections or the like at the open end, into holders. The tubes are fed one at the time from a supply into which the test tubes are placed directly from the packages to a means in which guide means retard the falling action of the end having the projections so that the closed end of the test tube falls faster and so that the test tube will be placed in a vertical position with the open end upwards, in a test tube holder placed directly beneath the falling path. When the next tube is fed also the next empty holder is fed into position.

DEVICE FOR AUTOMATIZED INSERTION F REACTION TUBES IN TEST TUBE HOLDERS BACKGROUND OF THE INVENTION Test tube holders are normally included as a part in conveyor units in equipment for automatized analysis. Reaction tubes have usually been inserted in these test tube holders manually, especially as the reaction tubes are generally packed by the manufacturer in boxes with the open end alternately in one or the other direction. This insertion has been tedious and is hardly consistent with the requirements of an analysis apparatus with otherwise automatized functions.

This invention relates to a device for automatized insertion of reaction tubes, having an enlarged outer diameter at the open end, into test tube holders.

The enlarged outer diameter at the open end of the test tube is normally some sort of projection, as, e.g., a bead, rim, flange, brim, lip or the like.

According to the present invention it has now been possible to automatize the insertion of reaction tubes, but these tubes must be provided with collars or similar projections at their open ends. The reaction tubes are placed parallelly to each other in a storage container and are fed to the test tube holders with the open end upwards independently if the tubes from the beginning have had their open end to one or the other side of the store container.

The present device comprises a supply means at the top for storing the reaction tubes in horizontal position, a feeding means under the supply means for passing one reaction tube at a time to means for turning the reaction tube to vertical position with the opening upwards and driving means for the feeding means, which driving means is controlled by one or several sensing means, the supply means consisting of two vertical support surfaces placed at angles to each other, whose ends near to each other are at such a distance from each other that an elongated opening with a width greater than the enlarged outer diameter of the reaction tube is formed and the turning means being limited by two walls forming a slit under the feeding means and with substantially the same width as the opening and the limiting walls in the slit being provided with lips preventing the fall of the open end of the reaction tube, and moreover with projections, which then guide the open end of the reaction tube towards a groove, through which the reaction tube falls with the open end upwards, and the whole insertion device being limited by vertical walls, which are at a distance from each other greater than the length of the reaction tubes. It is suitable that at least one of the support surfaces consists of conveyor belts, at least one of the conveyor belts feeding towards the operling. A suitable feeding means consists of a rotatable roller provided with one or several axial grooves adapted immediately under the opening between the support surfaces, each groove in this roller being adapted to contain only one reaction tube, which is fed to the slit by the rotation of the roller.

The feeding means for passing (locking) one reaction tube at a time generally consists of a room, which can be opened upwards as well as downwards. Upward or downward opening is however alternatingly effected so that at opening upwards a reaction tube falls down to the room and at opening downwards this reaction tube falls from the room down into the turning means. This embodiment having a roller provided with axial grooves is a suitable locking device of that type. Another embodiment of such aslocking device is a room, whose upper opening can be closed with a slide and whose lower opening can as well be closed with another slide. These slides must not be removed at the same time for opening the room but preferably alternatingly.

The walls limiting the supply means have been indicated to be plane, but it is obvious that these planes can also be bent.

The present device is thus built from five units, which in a preferred embodiment are as follows:

I. A supply means for reaction tubes.

This supply means (storage container) is designed so that two of the opposite sides of the container form inclined planes or support surfaces. One of these can take up a limit position as a horizontal plane and the other as a vertical plane. These planes or support surfaces have such a reciprocal distance that an elongated opening is formed between their lower edges, the

width of the opening being similar or somewhat greater than the outer diameter of the open ends of the reaction tubes. These two planes suitably consist of two conveyor belts which preferably move in the same direction. The storage containers are at the two sides limited by vertical walls, it, however, being clear that vertical must not be understood in the strict sense of the word, as they are preferably inclined so that a real "funnel is formed by the storage container. These walls are at a distance from each other that is greater than the length of the reaction tubes so that the reaction tubes can easily move between these walls. It is, however, clear that this distance must not be too great, i.e., preferably not more than about 5-10 mm. greater than the length of the reaction tubes, where the walls limit the opening.

2. A feeding means designed as a roller rotatable in the horizontal plane.

This roller is designed with one or several grooves (flutes) having such a depth and size that each groove makes room for a reaction tube. This roller is on its mantle surface enclosed by a cylindrical wall, which has two rectangular openings of such a size that they permit passage of a reaction tube. One of the openings is made in the upper mantle surface of the cylinder and one at the bottom. The roller need not be homogeneously built, but it is only required that grooves are formed there, in which the reaction tubes can be received and carried.

3. A driving means.

The driving means normally consists of an electrical motor, which is preferably placed on one side of the cylinder and attached so that its shaft can turn the rotatable roller enclosed in the cylinder.

4. A turning means.

This turning means consists of a cavity limited by vertical walls. Two of the four walls of the cavity are at a greater distance from each other than the outer diameter of the reaction tube but at a smaller distance than the open end outer diameter of the tube and the distance between the other two opposite sides is equal to or somewhat greater than the length of the reaction tubes. The upper edges of the two first-mentioned walls are designed so that their outer parts (i.e., the parts corresponding to the ends of the reaction tube) in the form of special fins are higher than at the center. These upper edges are thus inclined from both sides towards the center line. Around the center line material has been removed so that a circular flute is formed having a diameter permitting passage also of the enlarged diameter open end of the tube. As the distance between these two sidewalls is greater than the normal outer diameter of the tube but smaller than the enlarged diameter of the open end, free fall of the open end of a reaction tube inserted horizontally into the cavity is impeded. The enlarged diameter open end is forced to follow the upper edge from either of the two side projections down to the center line. Before the open end of the tube has reached the center line, the other part of the reaction tube has thus turned down between the limiting sidewalls. The tube has been oriented with its open end upwards. When the open end has reached the flute around the center line, the free fall of the reaction tube cannot be prevented. When falling, the tube is guided by the flute around the center line. As the device has been arranged so that its lower opening is in a position immediately over the test tube holder, for which the reaction tube is intended, the reaction tube is guided directly down into the test tube holder.

5. A sensing means.

The sensing means consist in this case of a photocell and lamp, the photocell and lamp being located respectively on opposing sides of the lower part of the flute around the center line in the turning means, as described in point 4. The

photocell actuates a relay function adapted to give impulses for starting and stopping the driving means referred to in point 3 above. At an impulse given to the relay function by another sensing means, for instance, upon sensing that an empty test tube holder has been placed'under the flute in the turning means, the driving means is started, for instance, by closing the circuit to the motor, and the feeding means (the roller) is turned until a tube, which has entered and been fed to any of the flutes of the roller, falls down through the lower opening of the cylinder and into the turning means referred to in point 4 above. The reaction tube is guided into the flute in the cavity around its center line. At the fall tube falls past the lamp, the strength of lightmeeting the photocell is reduced, and this decrease of light gives a new impulse to the relay function to stop the driving means, for instance, by breaking the current to a motor.

The means described under points I, 2 and 4 are combined with each other so that the storage container is at the top located of the assembly, under this is located the cylinder with the rotatable roller, and at the bottom is located the turning means adapted for guiding the reaction tube during its fall and taking the form of a room provided with two projections and a central flute. The connection between the storage container and the cylinder is formed by the opening in the storage container between the two planes and the upper opening in the upper mantle surface of the cylinder. The lower opening of the cylinder faces the upper edges of the turning means described under point 3.

The invention is more closely described with reference to the enclosed drawing, in which:

FIG. 1 shows schematically a side view of the device according to the invention.

FIG. 2 is a view along the line 2-2 in FIG. 1.

FIG. 3 is a part view of a device according to the invention as seen from the front.

In FIG. 1 planes or support surfaces 1, l are shown and an opening 8 situated between them. The plane 1 shown to the right in this figure consists here of a bent plane, whereas plane 1' shown to the left consists of a conveyor belt. It is understood that the storage container can also be restricted by another plane on its left side. Under the opening 8 there is a feeding means in the form of a roller 9, which is provided with grooves for reaction tubes. Under the feeding roller 9 there is a slit 7 with projection edges 6.

In FIG. 2 the turning means 12 itself with fins 3a and 3b and the projection edge 6 is shown, which limit the slit 7. In addition to this the central groove 5 can be seen.

In FIG. 3 the turning means is shown from the front. The fins 3a and 3b and the projection edges 6 located on the walls 2 appear clearly from this. The central groove 5 is also shown.

The device functions in the following way: Reaction tubes are manually placed in the funnel formed by the planes 1, l. The reaction tubes are inserted parallelly with the slit opening 8 and roll down into the slit opening. There is a certain risk that they may lock with each other. If the planes consist of conveyor belts, this risk is eliminated. In the embodiment shown in FIGS. 1-3 the reaction tubes fall in immediate sequence after each other through the slit opening 8 and are fed one at a time by the roller 9 down through the slit 7, where the enlarged diameter open end is stopped at its fall against either of the fins 3a and 3b. The other end continues its fall, the reaction tube thus being turned from horizontal to vertical position. The fin can no longer hold the enlarged diameter open end, and the open end of the tube accordingly slides along the projection 6 down to the groove 5. Independently of whether the opening of the reaction tube has been located to the right or to the left in FIG. I, the reaction tube will fall through the groove 5 with its opening upwards. It is for instance, possible to adapt the turning of the feeding roller 9 so that a reaction tube is fed as soon as a test tube holder has passed through the groove 5.

The walls limiting the funnel may be vertical or somewhat inclined outwardl frorn the opening/8 so that a real funnel is formed. The wal s lrmrtrng the slit are preferably vertical.

The width of slit 7 should be greater than the outer diameter of the reaction tube at the open end, and the distance between the projections 6 should be so great that the reaction tube in its entirety except the open end easily passes through. It must not be as great as the outer diameter at the open end. The opening 8 has preferably the same dimensions as the slit 7 or is possibly somewhat greater. The grooves 10 in the feed roller 9 must be so great that the reaction tube can be retained therein. It must, however, not be so great that two or more reaction tubes might be fed into the groove and possibly get jammed against the edge at the rotation of the roller. The feed roller 9 must of course not be as long as the slit 7 but must only comprise a part of this length. It can also be split and, for instance, consist of two narrow rollers located at some distance from either sidewall. These dimensioning questions must be decided in each case according to the dimensions of the reaction tube.

What I claim is:

I. In a device for automatic insertion of reaction tubes, having an enlarged diameter open end, into tube holders; comprising, supply means for storing the reaction tubes in horizontal position, feeding means under said supply means for passing one reaction tube at a time to turning means operative to turn the reaction tube to vertical position with the opening of said tube directed upwards, the supply means comprising two support surfaces placed at angles to each other, the ends of said surfaces closest to each other being at such a distance from each other that an elongated opening is formed there between having a width greater than the outer diameter of the reaction tube at the open end of the tube said turning means comprising two limiting walls forming a slit located under said feeding means and having substantially the same width as the opening, said limiting walls forming the slit being provided with fins positioned to temporarily impede the fall of the open end of the reaction tube and also being provided with projections positioned to guide the open end of the reaction tube towards a groove through which the reaction tube falls with its open end upwards, the entire insertion device being bounded by vertical walls which are spaced at a greater distance from each other than the length of the reaction tubes.

2. The device according to claim I, wherein at least one of said support surfaces comprises conveyor belts, at least one of same feeding towards said elongated opening.

3. The device according to claim I, wherein said feeding means comprises a rotatable roller provided with at least one axial groove, said roller being positioned immediately under the opening between the support surfaces each groove in the roller being adapted to contain only one reaction tube, said tube being fed to the slit by the rotation of the roller.

4. The device according to claim 2 wherein said feeding means comprises a rotatable roller provided with at least one axial groove, said roller being positioned immediately under the opening between the support surfaces, each groove in the roller being adapted to contain only one reaction tube, said tube being fed to the slit by the rotation of the roller. 

1. In a device for automatic insertion of reaction tubes, having an enlarged diameter open end, into tube holders; comprising, supply means for storing the reaction tubes in horizontal position, feeding means under said supply means for passing one reaction tube at a time to turning means operative to turn the reaction tube to vertical position with the opening of said tube directed upwards, the supply means comprising two support surfaces placed at angles to each other, the ends of said surfaces closest to each other being at such a distance from each other that an elongated opening is formed there between having a width greater than the outer diameter of the reaction tube at the open end of the tube said turning means comprising two limiting walls forming a slit located under said feeding means and having substantially the same width as the opening, said limiting walls forming the slit being provided with fins positioned to temporarily impede the fall of the open end of the reaction tube and also being provided with projections positioned to guide the open end of the reaction tube towards a groove through which the reaction tube falls with its open end upwards, The entire insertion device being bounded by vertical walls which are spaced at a greater distance from each other than the length of the reaction tubes.
 2. The device according to claim 1, wherein at least one of said support surfaces comprises conveyor belts, at least one of same feeding towards said elongated opening.
 3. The device according to claim 1, wherein said feeding means comprises a rotatable roller provided with at least one axial groove, said roller being positioned immediately under the opening between the support surfaces each groove in the roller being adapted to contain only one reaction tube, said tube being fed to the slit by the rotation of the roller.
 4. The device according to claim 2 wherein said feeding means comprises a rotatable roller provided with at least one axial groove, said roller being positioned immediately under the opening between the support surfaces, each groove in the roller being adapted to contain only one reaction tube, said tube being fed to the slit by the rotation of the roller. 